The present invention is directed to an anti-friction device with the use with material handling equipment, such as conveyors, work benches, work stations, carts, feed stations, or any equipment in which it is desirable to be able to use ball-type anti-friction elements to provide for change of direction of an object, moving along a conveyor or to provide a table on which an object can be moved and rotated to a desired orientation. A typical ball-type anti-friction device includes a housing which contains a relatively large ball that is supported on a plurality of smaller balls which enable the larger ball to rotate in any direction. The larger ball and smaller balls are mounted in a ball cage which is movably mounted within the housing for positioning the larger ball in either an inactive position in which the larger ball is below the upper surface of the housing and in an active position in which the larger ball extends above the upper surface of the housing. The movement of the ball cage is controlled by fluid drive means and biasing means.
An object of the present invention is the provision of a ball-type anti-friction device which has an improved actuating system for selectively positioning the larger ball in its lowered inactive position or in its raised active position.